Genes automate DNA machines

June 16/23, 2004

Scientists have been working with DNA with
an eye toward using it to make nanoscale machines that could eventually
work autonomously in environments like the human body.

Researchers from the University of Munich in Germany have taken
a step toward automating nanomachines with a method that allows instructions
for a DNA-based machine to be contained in a gene, or another stretch
of DNA.

The method could be used to automate any nanomachine that requires
fuel DNA to be added manually to start a reaction, according to the researchers.
The researchers built a DNA tweezer and a gene that closed the tweezer.

Genes work by transcribing instructions to a strand of messenger
RNA, which then translates the instructions into proteins that carry out
a function. The researchers' gene encoded an RNA fuel strand.

The method could be used to activate or block biological reactions
or produce reactions not found in nature, according to the researchers.

The method is a step toward DNA nanomachines that can operate
in living cells, but there's a lot of work to be done before this can
be realized, according to the researchers. The DNA machine and the gene
with the instructions for the machine would have to be delivered into
a cell simultaneously in a way that cells would not treat them as foreign
objects and destroy them.

The method could be used for practical applications in five to
ten years, according to the researchers. The work appeared in the April
14, 2004 issue of Nano Letters.